tests/subsys/mgmt/mcumgr: Move tests

Move smp_reassembly and zcbor_bulk tests under
tests/subsys/mgmt/mcumgr.

Signed-off-by: Dominik Ermel <dominik.ermel@nordicsemi.no>

tests/subsys/mgmt/mcumgr/smp_reassembly/src/main.c

@@ -10,7 +10,7 @@
 #include <zephyr/mgmt/mcumgr/smp.h>
 #include <zephyr/mgmt/mcumgr/buf.h>
 #include <mgmt/mgmt.h>
-#include "../../../../../subsys/mgmt/mcumgr/smp_reassembly.h"
+#include "../../../../../../subsys/mgmt/mcumgr/smp_reassembly.h"
 
 static struct zephyr_smp_transport zst;
 static uint8_t buff[CONFIG_MCUMGR_BUF_SIZE];